1. Field of the Invention
The present invention relates to a Lactobacillus plantarum strain and uses thereof, especially to an isolated Lactobacillus plantarum CMU995 and uses thereof.
2. Descriptions of the Related Art
Lactobacillus is one of the main bacteria existed in the intestinal tract of a human being or an animal. Due to the beneficial effects on the physiological activity of a human or an animal body, Lactobacillus is often added into various probiotic products. For example, Lactobacillus can inhibit the growth of enteric pathogens (such as Salmonella or Escherichia) or resist pathogen invasion, for instance, preventing an invasion of Salmonella typhimurium to the gastrointestinal epithelial cells.
Currently, there are many patents relating to the applications of Lactobacillus for inhibiting pathogens. For example, U.S. Pat. No. 5,603,930 discloses a Lactobacillus johnsonii that can inhibit enterotoxin and intestinal invasive pathogens; U.S. Pat. No. 3,953,609 discloses a Lactobacillus lactis that can inhibit the growth of Escherichia in the digestive system; and U.S. Pat. No. 6,491,956 discloses a Lactobacillus acidophilus that can prevent and treat gastritis, duodenal ulcer, and gastric ulcer caused by Helicobacter pylori infection.
Apart from basic physiological/pharmacological activity, Lactobacillus must have two important characteristics to function effectively within the animal body. Firstly, the Lactobacillus must have strong tolerance to the gastric acid and choline secreted by the animal gastrointestinal tract in order to survive in the digestive system and reach to the intestinal tract to serve its function. Then, the Lactobacillus must be able to strongly adhere to the intestinal epithelial cells of an animal host to compete with other pathogens in the gastrointestinal tract and avoid being expelled by the pathogens. In addition, because pathogens also infect the animal body by adhering onto the intestinal epithelial cells, if the Lactobacillus has a relatively strong adhesion ability to the intestinal epithelial cells, then it can expel the pathogens to protect the gastrointestinal tract from being infected.
The inventor of the present invention screened a novel strain of Lactobacillus plantarum from the excretion of newborn babies, and through relative in vivo and in vitro experiments, found that apart from inhibiting pathogens, the Lactobacillus plantarum has excellent adhesion ability to the cells of the gastrointestinal tract and the urinary tract, and therefore can effectively and durably protect the gastrointestinal tract and the urinary tract from pathogenic infections. The inventor also found that this strain can directly inhibit the growth of pathogens to prevent and treat diseases caused by the pathogens.